Autonomic Nervous System II

What does the Sympathetic NS do for the blood vessels?

Innervates smooth muscle of vessles

Normalizes basal sympathetic tone (BP)

There is ______ innervation to the vasculature but presents of uninnervated ____ receptors in the endothelium?

NO parasympathetic

M receptors

Epinephrine and Norepinephrine will have an ____ effect in the blood vessels of the skin and reservoir veins causing them to ____?

Equal effect

Vasoconstriction

What kind of receptor is in the blood vessels of the skin and reservoir veins? What kind of secondary messenger do we use?

Alpha 1

Gq - ca2+ contract muscles

What kind of receptors do we find in blood vessels of the skeletal muscle?

A1 and B2

What will A1 and B2 respond to in the blood vessels of the skeletal muscle?

A1 - NE - vasoconstriction

- E in high concentrations - vasoconstriction

B2 - E in low concentrations - vasodilation

What receptors are on blood vessels of the viscera and renal systems?

A1

B2

DA

What will A1, B2 and DA respond to in the blood vessels in the renal and visceral?

A1 - NE - Vasoconstriction

- E hight levels - vasoconstriction

- DA high levels - vasoconstriction

B2 - E low levels - vasodilation

DA - Dopamine low levels - Vasodilation

What factors will control MAP?

CO and Peripheral vascular resistance

Parasympathetic innervation of the heart will ____ MAP by doing what?

Reduce by reducing CO via slowing HR

How does sympathetic innervation to the heart ____ MAP?

Increase MAP by increasing contractility of ventricles and HR by innervating the nodes (all increase CO), Also can see an increase in peripheral resistance Via A1 depending on stimuli

Norepinephrine can increase what in the CV system?

HR, Contractility, and MAP

What receptors are more sensitive to NE?

Alpha receptors

What receptor does NE act on in the heart to increase contractility and HR?

B1

Where are Baroreceptor's located?

carotid bodies and aortic arch

Explain how the baroreceptor reflex would respond to arterial pressure increase?

Carotid or aortic arch would send afferent signal to medulla that would decrease parasympathetic impulses and increase sympathetic impulses

Why does decreasing sympathetic impulses to the vasculature result in vasodilation?

Decreased signaling leads to less constriction, No parasympathetic innervation to blood vessels

What does the parasympathetic NS do to the respiratory system?

Vagus innervates M receptors causing bronchoconstriction and mucus secretion

What kind of sympathetic receptor do we see in the lungs and what does it cause?

B2 receptors

Bronchodilatory

What does the parasympathetics do for the GI system?

Stimulates GI motility, gastric acid secretion and, intestinal motility

What does the sympathetic NS do for the GI system?

Reduction of GI motility,

Increase Glycogenolysis

Increase islet cells of pancreas

Increased lipidolysis

Why might we increase islet cells in the pancreas in the sympathetic NS?

Increase sugar intake into skeletal muscle

Why does Pyridostigmine bromide cause Intussusception?

Blocks Acetalcolinestrase in the gut before being absorbed resulting in more Ach which signals M receptors leading to increased GI motility

What does parasympathetics do for the genitourinary system?

Erection

Urination

What does Sympathetics do for the genitourinary system?

Uterine contractions

Ejaculation

Increase renin

Prevent urination

What does the parasympathetic NS do for the eyes?

Increased tears,

Accommodation of lens for near objects

Miosis - pupil constriction

Parasympathetics on the eye will open the _____ chamber which will do what?

Anterior chamber angle to let aqueous humor drain from the canal of scheme to decrease Intraocular pressure

What will the sympathetic NS A receptors do for the eye?

Mydriasis - dilate pupil

NO accommodations

What will the sympathetic NS B receptors do for the eye?

Increase Aqueous humor production raising intraocular pressure

Accommodation for distant objects

In the spleen a-mediated sympathetic stimulation will cause ______. B-mediated will cause ___?

Contraction

Relaxation

Sweat gland sympathetics are modulated by ___ in most species but __ in horses?

Cholinergic

B2

Piloerector muscles are controlled by what sympathetic receptor?

Alpha mediated contractions